Permanent type foundations for manufactured housing are becoming more desirable and more prevalent as the housing structures become larger, more expensive, and better suited to long term financing. There are a number of permanent foundation systems being used for manufactured housing, including one produced by this inventor, the subject of a patent application filed Mar. 30, 1987, Ser. No. 07/031,741, now U.S. Pat. No. 4,793,110.
Several of these systems use a stanchion arrangement having an extended base means which is attached to a concrete foundation member by means of four anchor bolts embedded in the concrete member. In this arrangement, insertion of the stanchion after the structure is in place and fully lowered is not possible because of the protruding anchor bolts.
A two inch height adjustment range, along with a series of stanchion sizes, is designed to allow support at any height within a predetermined range of support heights. However, it is necessary, when using one of these systems, to place the structure over the concrete foundation members, level it and determine the height necessary at each stanchion, and then raise the structure by two or three inches in order to insert the stanchions over the anchor bolts, after which the structure is lowered again.
Another method sometimes used involves the placement of the structure in the proper location but not lowered, after which the stanchions are chosen for proper height by use of an extended water level, and attached to the anchor bolts, and the structure is then lowered and attached to the stanchions. There is a flaw in this method in that the structure's longitudinal support members are usually not perfectly straight, and sometimes the structure must be raised again to change one or two stanchions to a different size.
Height adjustment is most often accomplished by means of a vertical, threaded support member having some type of securement means at its upper end. Because of the lateral wind forces applied to the upper end of the vertical support member, it must be relatively large. The design load to be borne vertically by the vertical support member is also a factor, particularly if the load is applied at even an inch removed from the vertical axis of the vertical support member.
An ideal stanchion system, and one not found in the art, is one which would furnish four to six inches of vertical adjustment on each stanchion, thereby limiting the inventory required to handle most any installation, to three or four stanchion sizes. Further, the ideal stanchion would be insertable after the structure is permanently lowered, without losing any of its height adjustment capacity.
Most systems currently available have a somewhat limited lateral adjustment capability, usually on the order of three inches total. This is usually provided for by connecting the anchor bolts into slots in the stanchion base. These slots weaken the base and make necessary the use of a heavier material. When more lateral misallignment of the anchor bolts and the structure's longitudinal support member must be accommodated, it is furnished by supporting the structure's longitudinal support member off-center on the vertical support member of the stanchion. This off-center loading reduces the capacity of a given size vertical support member, making the size prohibitive for a member which would afford the desired large height adjustment.
In order for a stanchion system to economically furnish the desired large vertical adjustment, it is then a requirement that the base and body portion of the stanchion furnish an adequately large lateral adjustment capability, so that the stanchion's vertical support member can be centered exactly under the structure's longitudinal support member. The ideal stanchion must also be adapted to placement without loss of height adjustment capability, and without an extra lowering and raising of the structure, or the time consuming use of a water level.
None of the stanchion type support units on the market or known in the patent art at present possesses these desired features.